William Barr will appear before the Senate Judiciary Committee today as President Trump‘s nominee to replace Jeff Sessions as Attorney General of the United States. The hearing is scheduled to begin at 9:30 a.m. ET.

Barr has a high probability of confirmation in the Republican-controlled Senate, but its possible he’ll be grilled by Kamala Harris, Cory Booker, and other committee Democrats believed to hold presidential ambitions. Since Robert Mueller will undoubtedly be a major flashpoint of the hearing, it’s virtually assured Barr will be asked for how he will oversee the ongoing investigation of Russia’s meddling with the 2016 election.

Back in 2018, Barr wrote a memo in which he criticized Mueller’s “fatally misconceived” obstruction theory and said Trump should not be forced to take questions from the special counsel. The counterpoint is that Barr released a series of written remarks ahead of his testimony, saying Mueller should be allowed to finish his investigation unimpeded, and the results should eventually be released to the public.

“I also believe it is very important that the public and Congress be informed of the results of the special counsel’s work,” Barr says. “For that reason, my goal will be to provide as much transparency as I can consistent with the law.”